Retractable bollards have posts that can be raised for blocking vehicular traffic or lowered flush to the floor to allow traffic to pass. Retractable bollards can be used on roadways, driveways, loading docks, rail or finger docks, factories, and warehouse floors. Examples of retractable bollards are disclosed in U.S. Pat. Nos. 8,096,727; 6,955,495; 6,345,930; 5,476,338; 5,365,694; 5,054,237; 4,919,563; 4,715,742; 4,576,508; 4,003,161; 3,698,135; and 3,660,935. Each of the bollards described in these patents has one or more limitations such as complexity, manufacturing cost, durability, replaceability, and/or single purpose functionality.